Abstract/Description

A new method for controlling the tsetse fly is currently being tested. The tsetse fly is responsible for transmitting the potentially fatal disease sleeping-sickness in humans, and the similar disease, nagana, in cattle. The new method uses the...

Notes

A new method for controlling the tsetse fly is currently being tested. The tsetse fly is responsible for transmitting the potentially fatal disease sleeping-sickness in humans, and the similar disease, nagana, in cattle. The new method uses the same type of cloth trap or target that is currently in use but instead of impregnating the fabric with pyrethroids, this new method uses pyriproxyfen.
Within five seconds of landing on the cloth trap, a female fly nicks up a dose of the chemical. This mimics the action of the juvenile hormones, effectively sterilizing the fly. Half to three quarters of the resulting larvae fail to metamorphose. After two minutes in contact with the cloth no larvae develop. Although pyriproxyfen does not sterilise male flies, once contaminated they can transfer a sterilizing dose to the females during mating.
Pyriuroxyfen not only sterilizes the female flies but it also has a very low toxicity to other living things and is very stable. In a recent field trial in the Zambezi Valley of Zimbabwe, treated
fabric was capable of sterilizing female flies nine months after the original treatment. The traps impregnated with the pyrethroids that are currently used would have lost all activity by that time.
Professor PA Langley
Insect Investigations
Langford House
Langford Nr Bristol BS18 7DY